The present invention relates to a method which facilitates the concurrent non-destructive evaluation of partially completed welds.
Thick sectional welds are usually made in several passes. In this regard, it should be understood that the area between two adjacent parts to be joined is filled up a portion at a time. In testing of such thick sectional welds, ultrasonic sensors and other non-destructive evaluation methods are often used to inspect same. However, under most operational circumstances, these inspections have been done heretofore at some time period after the welding has been completed and the weld has cooled down. It has long been known that when welding defects are detected on a pass-by-pass basis, they can be easily repaired before being covered by the welding material laid down by subsequent welding passes. Thus, for example, a defect in the root pass can be repaired easily and economically without grinding out all the welding metal from the later passes. This welding method contrasts with inspecting a completed weld because a significant amount of weld material may have to be subsequently removed to reach the welding defect. Still further, and as discussed in U.S. Pat. No. 4,712,722, a significant economic and productivity advantage can be obtained if welding flaws can be substantially concurrently detected and repaired on a pass-by-pass basis.
As noted further in our application Ser. No. 09/583,632 from which we claim priority, it has been discovered that for inspection of welds to be accurate, the movement of ultrasonic sensors must be synchronized within small tolerance parameters.
In view of the foregoing, it would be highly desirable to provide a method for the concurrent ultrasonic inspection of partially completed welds which achieves the benefits to be derived from the aforementioned technology but which avoids the detriments individually associated therewith.
Therefore, one aspect of the present invention is to provide an improved method for the concurrent ultrasonic inspection of partially completed welds.
Another aspect of the present invention is to provide a method for the concurrent ultrasonic inspection of partially completed welds which includes the steps of providing a pair of transducers which are individually positioned on the opposite sides of a partially completed weld to be inspected; moving the transducers along the length of and laterally inwardly and outwardly relative to the partially completed weld; pulsing the respective transducers to produce an ultrasonic signal which passes through or is reflected from the partially completed weld; receiving from the respective transducers ultrasonic signals which pass through or are reflected from the partially completed weld; and analyzing the ultrasonic signal which is passed through or is reflected from the partially completed weld to determine the presence of any weld defects.
Another aspect of the present invention is to provide a method for the concurrent ultrasonic inspection of partially completed welds which includes providing a pair of transducers which are individually positioned on the opposite sides of a partially completed weld which is to be inspected; providing a pair of motors which are individually disposed in driving relation relative to each of the transducers; providing a controlling computer having executable programming for selectively controlling the movement of each of the motors; energizing the respective motors with a controlling computer to cause the respective transducers to travel in a predetermined synchronous pattern of motion; pulsing the respective transducers with a controlling computer to produce an ultrasonic signal which is reflected from or which passes through the weld which is being inspected while the transducers are being moved in the predetermined synchronous pattern of motion; and analyzing the ultrasonic signal which is reflected from or which passes through the partially completed weld by the controlling computer to determine the presence of any weld defects.
Still further, another aspect of the present invention is to provide a method for the concurrent ultrasonic inspection of partially completed welds wherein the method employs a controlling computer which includes a pair of pulser/receivers which are controlled by the controlling computer, and which are individually electrically coupled with each of the transducers; an analog to digital converter controlled by the controlling computer and which receives the ultrasonic signal which passes through or is reflected from the partially completed weld being inspected; and an analog and digital input/output assembly controlled by the controlling computer and which is coupled in signal transmitting relation relative to the pair of pulser/receivers and which generates a signal causing the pair of pulser/receivers to produce a pulse, and wherein the signal further causes the analog and digital converter to receive the ultrasonic signal.
Still another aspect of the present invention relates to a method for the concurrent ultrasonic inspection of partially completed welds wherein the controlling computer energizes each of the motors in a manner to cause the substantially synchronous movement of each of the transducers along a predetermined path of travel.
Yet still further, another aspect of the present invention relates to a method for the concurrent ultrasonic inspection of partially completed welds wherein the computer, having executable programming, coordinates the pulsing of the respective transducers during the movement of the respective transducers along the path of travel, and wherein, the controlling computer determines the predetermined locations.
Another aspect of the present invention is to provide a method for the concurrent ultrasonic inspection of partially completed welds wherein the step of analyzing the ultrasonic signal occurs following the completion of the movement of the respective transducers.
These and other aspects of the present invention will be discussed hereinafter.